The invention generally relates to paint spray booths. More particularly, the invention concerns paint spray booths utilizing longitudinal exhaust air flow through the booth from both ends thereof towards a centrally located exhaust system.
Designers of conventional paint spray booths have traditionally attempted to deal with improving paint transfer efficiency therein. Much of the paint spray, especially in powder spray booths, never reaches the target being painted and becomes so-called "overspray" which must be removed from an air stream in the booth. Overspray, in turn, leads to build up problems on booth walls surrounding the paint spray application area. Cleaning the booth walls in this area typically has required costly shut down of the spray booth for manual cleaning of its interior walls.
One known approach to minimizing overspray buildup in a powder spray booth is taught in U.S. Pat. No. 3,921,576 to Vertue, wherein the spray chamber is surrounded by porous walls through which a gas, such as air, passes to counteract deposition of paint powder on the wall, thus facilitating cleaning of the booth. A similar concept is taught in U.S. Pat. No. 3,741,155 to Hunder. However, neither the Vertue nor the Hunder patents suggest use of the inward air flow through the porous walls to increase paint transfer efficiency by directing variably controlled air flow through the porous wall toward the object being painted.
Additionally, none of the art presently known to applicant utilizes exhaust air flow through a paint spray booth which exits the booth other than through a conventional grated flooring thereof.